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1.
Investigation of the mean free path of projectile fragments produced in 16O-Em collision at 60 A GeV 下载免费PDF全文
Results are presented for an investigation of the mean free path of projectile fragments with charge 3≤Z≤8, produced by 60 A GeV {}^{16}O in nuclear emulsion. No dependence of mean free path on the distance from the point of the fragment emission is observed and our result is consistent with the nonexistence of anomalons. 相似文献
2.
A density functional theory investigation on a series of sandwich-type transition metal complexes [(CBO)n]2M (n=4–6; M=transition metals) with carbon boronyls (CBO)n as effective aromatic ligands has been presented in this work at B3LYP level. The ground-states of these complexes possess staggered Dnd symmetries, while the corresponding eclipsed Dnh structures exist as transition states with slightly higher energies (within 5.8 kJ/mol). Carbon boronyl complexes [(CBO)n]2M are confirmed to be much more stable than their boron carbonyl isomers [(BCO)n]2M, which, on the other hand, take eclipsed ground-states with Dnh symmetries. The carbon boronyl complexes [(BCO)n]2M proposed in this work parallelize the well-known sandwich-type hydrocarbon complexes [CnHn]2M in coordination chemistry with boronyl groups –BO isolobal to –H atoms in corresponding ligands. 相似文献
3.
We study level surfaces of non-degenerate functions inR
n+1. Such level surfaces are non-degenerate in the sense of affine differential geometry. In affine differential geometry, the affine normal plays an important role for the study of a non-degenerate hypersurface. In this note, being motivated by Koszul's work we take a canonical vector field
for level surfaces of a non-degenerate function and give certain characterizations of when
is transversal, by the shape operatorS, the transversal connection , and consider the difference between
and the affine normal. 相似文献
4.
5.
Tetradecker transition metal complexes containing double planar hexacoordinate carbons and double planar heptacoordinate borons 总被引:1,自引:0,他引:1
A theoretical investigation on tetradecker transition metal complexes of Cp-Fe-CB6-Fe-CB6-Fe-Cp (1) containing double planar hexacoordinate carbons and Cp-Fe-BB7-Fe-BB7-Fe-Cp (2) containing double planar heptcoordinate borons has been performed in this work at density functional theory level. [CpFe]+ monocations prove to effectively stabilize these unusual complexes, which are mainly maintained by effective d-pi coordination interactions between the partially filled Fe 3d orbitals and the delocalized pi molecular orbitals (MOs) of the four planar deckerlike ligands. The results obtained in these model computations expand the domain of ferrocene chemistry and could provide a new approach for synthesizing planar hyper-coordinate carbons and borons in transition metal complexes. 相似文献
6.
The measurements of partial production cross sections of the multiple helium projectile fragments emitted at 4.5 A GeV/c {}^{16}O-Em interactions are reported. We have studied the production rate of helium projectile fragments due to fragmentation of {}^{16}O ions and compared it with that obtained from different projectiles at various energies. The dependence of on the mass number of the incident beams is formulated. The multiplicity distributions of the helium fragments produced in {}^{16}O-Em interactions at different energies exhibit Koba-Nielson-Olesen (KNO) scaling. The correlation of helium projectile fragments and target fragments is also investigated and it is found that the average of target fragments is increased with the decrease of the number of helium fragments in peripheral interactions. 相似文献
7.
We present the topology of 16O fragmentation at 60A GeV in reactions with emulsion nuclei.We discuss the multiplicity distributions of projectile fragments.charged secondaries and their dependence on the target residues. 相似文献
8.
Existence of solutions to a class of nonlinear second order two-point boundary value problems 总被引:2,自引:0,他引:2
Fuyi Li Zhanping Liang Qi Zhang 《Journal of Mathematical Analysis and Applications》2005,312(1):357-373
In this paper, the existence and multiplicity results of solutions are obtained for the second order two-point boundary value problem −u″(t)=f(t,u(t)) for all t∈[0,1] subject to u(0)=u′(1)=0, where f is continuous. The monotone operator theory and critical point theory are employed to discuss this problem, respectively. In argument, quadratic root operator and its properties play an important role. 相似文献
9.
A density functional theory investigation on a series of S-shaped or cyclic (BnEmSi)2H2 molecules (E = B, C, Si; n = 3-6; m = 1, 2) containing double planar tetra-, penta-, and hexacoordinate silicons has been presented in this work. Further theoretical evidence is provided to support the previously proposed structural pattern to host planar hypercoordinate silicons in small aromatic molecules. 相似文献
10.